In situ study of the crystallization process and magnetism in some FeNbSiBCu amorphous alloys

Neutron diffraction between RT and 1000 degrees C has been employed to determine the crystalline phases appearing during the crystallization of Fe77Nb4Cu1SixB18-x(x = 0,12) metallic glasses. In the sample without Si(x = 0), the predominant phase is BCC-Fe, while in the x = 12 sample an FCC-FeSi with DO3-type structure is building up from the beginning of the crystallization process. For temperatures above 910 degrees C, the BCC-Fe phase transforms its structure to FCC-Fe in the x = 0 sample. However, the FCC-FeSi phase remains stable in the x = 12 alloy in the studied temperature range. The thermal expansion of the lattice parameters lies around 1% while the total intensity decreases around 10% for all the phases.